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    <title>coffg</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>coffg</b> -  inverse of polynomial matrix</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>[Ns,d]=coffg(Fs)   </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>Fs</b>
        </tt>: square polynomial matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>coffg</b>
      </tt> computes <tt>
        <b>Fs^-1</b>
      </tt> where <tt>
        <b>Fs</b>
      </tt> is a polynomial
    matrix by co-factors method.</p>
    <p>
      <tt>
        <b>Fs</b>
      </tt> inverse = <tt>
        <b>Ns/d</b>
      </tt>
    </p>
    <p>
      <tt>
        <b>d</b>
      </tt> = common denominator; <tt>
        <b>Ns</b>
      </tt> =  numerator (a polynomial matrix)</p>
    <p>
    (For large matrices,be patient...results are generally reliable)</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

s=poly(0,'s')
a=[ s, s^2+1; s  s^2-1];
[a1,d]=coffg(a);
(a1/d)-inv(a)
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="determ.htm">
        <tt>
          <b>determ</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="detr.htm">
        <tt>
          <b>detr</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="invr.htm">
        <tt>
          <b>invr</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../linear/penlaur.htm">
        <tt>
          <b>penlaur</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../linear/glever.htm">
        <tt>
          <b>glever</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Author</font>
    </h3>
    <p>F. D.; ;   </p>
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